Textile yarn sizing process



United States Patent 3,055,772 TEXTILE YARN SIZING PROCESS SimpeyKuramoto, St. Louis Park, Miun., assignor to General Mills, Inc., acorporation of Delaware No Drawing. Filed Dec. 1, 1960, Ser. No. 72,8636 Claims. (Cl. 117--139.5)

This invention relates to a novel textile sizing process.

In the weaving of yarns into fabrics, most yarns lack the strength andabrasion resistance necessary to weave efficiently under typical weavingconditions. To overcome these deficiencies, yarns are impregnated with amaterial called size. Generally, the size is removed at the end of theweaving operation to yield a size-free fabric. Thus, it is importantthat the size lend the necessary strength and abrasion resistance and bereadily removable from the fabric. Since end breaks are inevitable, endsthat do break should be free of fuzz balls so that further weaving isnot suspended in any way.

It is an object of this invention to provide a novel process for sizingtextile yarns. It is another object of this invention to provide asizing process wherein the size is easily removed. It is a furtherobject of this invention to provide a yarn which is abrasion resistantand which weaves efiiciently. Other objects will appear hereinafter.

The objects of this invention are accomplished by the process whichcomprises impregnating a textile yarn with cyanoethylated gluten andrecovering a strong, abrasion resistant yarn obtained thereby. Inaccordance with the present invention, it was discovered thatcyanoethylated gluten provides an excellent sizing compound for yarns.

As used herein, the term cyanoethylated gluten refers to the reactionproduct under aqueous alkaline conditions of gluten and acrylonitrile.This product may be prepared by reacting an aqueous alkaline glutensolution with acrylonitrile at room temperature. Details of such apreparation are described in U.S. 2,562,534, granted to John RobertCofiman on July 31, 1951.

Virtually any yarn may be sized by this process. Since excellent resultsare normally obtained with extremely inexpensive sizing agents in thecase of natural fibers, the present invention is most useful in thesizing of synthetic fibers. Synthetic fibers generally are much moredifficult to size than natural fibers due to the generally inertchemical composition and smooth physical structure of synthetic fibers.Typical synthetic fibers which are suitable for use in the presentinvention include cellulose acetate fibers, polyester fibers andpolyamide fibers.

The sizing composition of the present invention may be applied to theyarn in a variety of ways. Generally, these methods are very Well knownin the art. A preferred method consists of passing a yarn through asolution of the size, subjecting the yarn to pressure to squeeze out theexcess size and subsequently drying to remove the size solvent. Theprocess of applying size is referred to as slashing, by those in theart.

The size of the present invention is easily removed by washing in adetergent. Other methods of removing the size such as by enzymaticaction may be employed if desired. In some instances, it is notdesirable to remove the size, and here, the present size may be left onthe yarn with no particular disadvantage.

The amount of size employed is not critical. Some improvement in weavingqualities is obtained even when extremely low concentrations of thesizing agent are employed. Generally, it is uneconomical and unnecessaryto employ extremely large amounts of size. Normally, 4 to 8% by weightof the size, based on the weight of the yarn, is preferred. The amountof size employed is conveniently controlled by controlling theconcentration of the above cellulose acetate as fill.

Ice

size in the sizing solution and by removing excess solution by means ofsqueeze rolls. The use of squeeze rolls is preferred in any event inorder to obtain more uniform impregnation of the yarn.

The size is most conveniently applied as an aqueous solution. It will beunderstood that the solution is actually a collodial dispersion althoughgenerally referred to as solutions by those in the art. Preferably thesolution contains 5 to 15% by weight of the cyanoethylated gluten. Othersolvents may also be employed to dissolve the sizing agents if desired.The size may be applied to the yarn initially but is more convenientlyapplied after the yarn has been made into a warp.

Generally, better results are obtained when a small amount ofplasticizer is added to the yarn along with the sizing agents. Theplasticizer yields a more flexible coating of the sizing agent. Theplasticizer employed is not critical. Preferred plasticizers are theglycols such as ethylene glycol, glycerin propylene glycol, and esterssuch as butyl adipate.

Sizing is best carried out at temperature somewhat above roomtemperature. The preferred conditions are from to F. Higher temperaturemay be employed, but to no substantial advantage.

After slashing, the wet yarn is dried. This may be done by passing thetreated yarn through a heated oven. A preferred method is to pass theyarn over a series of heated rolls or cans as they are referred to inthe art. A series of these cans are placed substantially side by sideand the yarn passed over one can and under the next etc.

The following examples are included to illustrate various features ofthe present invention and the preferred embodiments thereof.

Example I A 210 end warp having 143 ends per inch was prepared from 75denier cellulose acetate yarn having 20 filaments per end and 5 twistsper inch with a Z twist. The warp was passed through an aqueous solutionat 110 F., containing 9% by weight, based on the total composition, ofcyanoethylated gluten and 1% by weight, based on the total compositionof glycerin. The warp was passed through squeeze rolls and dried bypassing over, under, etc., four rollers heated to F., F., 180 F., and160 F., respectively. The sized warp which retained 8.5% by weight, ofthe size, was woven on a Draper XD loom operating at 172 picks per inchusing Fifty yards of fabric were woven. There were 0.5 stop per tenyards on warp and no stops on the weaving. There were no thread breakson the slashing step and 2 breaks on the weaving due to brokenfilaments. The picks per inch were 102% of the calculated concentration.The weaving efficiency was calculated as 85%.

Example II A 5600 end warp having 136 ends per inch was prepared from 75denier cellulose acetate yarn having 20 filaments per end and 5 twistsper inch with a Z twist. The warp was slashed as in Example I with anaqueous sizing solution at 140 F. containing 6.48% by weight, based onthe total composition, of cyanoethylated gluten and 0.72% by weight,based on the total composition, of glycerin. After passing throughQuetsch rolls which exerted 1200 psi. pressure on the warp, the slashedwarp was dried and fed to a Draper XD loom operating at a fill densityof 172 picks per inch using the above cellulose acetate as fill. Thewarp retained 5.4% by weight, of the size. The material shed from theweaving operation was collected and found to be 4.5 grains per 10 yards.Dur

3 ing the weaving of fifty yards of the fabric there were 2.2 loom stopsper ten yards for the warp and no stop on the filling. In the 50 yardsthere were breaks on the slashing operation and 11 breaks on the weavingdue to broken filaments. The weaving efficiency was calculated as 93.8%.

The foregoing examples are not to be interpreted as limitations on thescope of the present invention. Numerous variations will be apparent tothose skilled in the art.

The process of the present invention is useful in producing sized yarnhaving improved weaving qualities.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. The process which comprises impregnating a textile yarn withcyanoethylated gluten, drying the yarn, and recovering a strong,abrasion resistant, sized yarn obtained thereby.

2. The process of claim 1 wherein the yarn is simultaneously impregnatedwith a plasticizer.

3. The process of claim 1 wherein the yarn is a cellulose acetate yarn.

4. The process of claim 1 wherein the textile yarn is polyesterfilament.

5. The process of sizing synthetic textile yarn which comprises passingsaid yarn through an aqueous solution of glycerin and cyanoethylatedgluten, removing said yarn from said solution, drying the yarn, andrecovering a strong, abrasion resistant, sized yarn obtained thereby.

6. A sizing composition consisting essentially of an aqueous solution ofcyanoethylated gluten and a plasticizing amount of glycerin.

References Cited in the file of this patent UNITED STATES PATENTS2,562,534 Cofiman July 31, 1951

1. THE PROCESS WHICH COMPRISES IMPREGNATING A TEXTILE YARN WITHCYANOETHYLATED GLUTEN, DRYING THE YARN, AND RECOVERING A STRONG,ABRASION RESISTANT, SIZED YARN OBTAINED THEREBY.